Device for controlling the level of liquid metal in a casting container

ABSTRACT

A casting system having a container for a liquid casting material comprising a receiving or entry chamber and an exit or dispensing chamber, a passage interconnecting the entry and exit chambers at their bottom portions, means for supplying a gaseous medium under pressure to the entry chamber for translating the liquid metal between the entry and exit chambers and for regulating the level of the liquid metal therein at a predetermined constant level, the liquid metal in the entry chamber being disposed at a level below the bottom of the exit chamber, and a controllable stopper arrangement disposed in the exit chamber for controlling the dispensing of the liquid metal therefrom.

United States Patent 1 Wernli etal.

[Ill 3,729,118

45} Apr. 24, 1973 DEVICE FOR CONTROLLING THE 3,504,825 4/1970 Diamond et al. ..l64/l56 x LEVEL OF LIQUID METAL IN A CASTING CONTAINER FOREIGN PATENTS OR APPLICATIONS 75 Inventors: Max W H Tanner, both of 902,430 l/l954 Germany ..222/DlG. l5

Schaffhausen, Switzerland Primary Examiner-Robert D. Baldwin [73] Assignee: Erwin Buhrer, schaffliausen, Sw 1t- Atmmey EmeSt R Marmorek zerland [22] Filed: June 1, 1971 ABSTRACT [211 App]. No.: 148,634 A casting system having a container for a liquid casting material comprising a receiving or entry chamber d an exit or dis ensin chamber a assa e intercon- 30 F P g t P g orelgn Apphcanon Pnonly Data necting the-entry and exit chambers at their bottom June 1, 1970 Switzerland....'. ..8l50/70 portions, means for supplying a gaseous medium 3 under pressure to the entry chamber for translating [1.8. CI- the meta] between the entry and exit chambers 222/373 and for regulating the level of the liquid metal therein [51] Int. Cl. ..B22d 37/00 at a predetermined constant level the liquid meta] in [58] Fleld of Search ..l64/l55, 156, 28L the entry chamber being disposed at a level below the 164/337 ZZZ/DIG 3 DIG' 394 bottom of theexit chamber, and a controllable stopper arrangement disposed in the exit chamber for [56] References Cited controlling the dispensing of the liquid metal UNITED STATES PATENTS therefrom- 3,384,l50 5/1968 Newsome ..l64/l55 4 Claims, 3 Drawing Figures Z9 Z7 t j i j; m t 1?) Patented April 24, 1973 3,729,118

5 Sheets-Sheet 1 INVENTORS:

W 44 cud imp-M,

Patented April 24, 1973 3 Sheets-Sheet f.

Patented April 24, 1973 3 Sheets-Sheet I DEVICE FOR CONTROLLING THE LEVEL OF LIQUID METAL IN A CASTING CONTAINER FIELD OF THE INVENTION The present invention relates to a device for the level control of a liquid metal in a casting material container in which the liquid metal by means of the pressure of a pressurized medium is translated from an entrance or filling chamber into an exit or dispensing chamber connected with the former, and in which the liquid metal under the influence of the controllable pressure of the pressurized medium is retained constant at a predetermined level in the filling or entrance chamber.

BACKGROUND OF THE INVENTION In general, the device of the above mentioned type is intended to keep the exit velocity of the liquid metal flowing to the mold during the casting process at a predetermined constant value.

Devices are known in which from the cast container the liquid metal is transferred by means of pressurized air into a saucer-shaped casting arrangement or by means of a pouring device the liquid metal is transferred from an intermediate container. Furthermore, devices are known in which quantities of the molten material can be taken off from the cast material containerhaving a stopper arrangement and connected with an intermediate container.

The known devices have their disadvantage in that the level of the liquid metal cannot be kept constant and, as a result, the exit velocity decreases, as well as time consuming precautions are necessary in order to clear the exit chamber during interruption of the operation.

BRIEF SUMMARY OF THE INVENTION It is, therefore, an object of the present invention to provide an improved casting arrangement which does not possess the above-described disadvantages of known devices and in which the level of the liquid metal can be kept constant independently from the quantities removed and, at the same time, a slag-free casting of the material is possible.

Accordingly, the present invention provides a casting arrangement in which a fill-in or receiving chamber is provided and which is situated lower than the bottom ofthe exit or dispensing chamber, a passage connecting the receiving or entrance chamber with the exit or dispensing chamber and particularly connecting the bottom portions of both chambers, a dispensing stopper arrangement provided in the exit or dispensing chamber, and means for controlling and retaining the level of the liquid metal constant in the exit chamber and thereby the exit velocity of the metal during the casting process.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will become more readily apparent from the following description of preferred embodiments thereof shown in the accompanying drawings, in which:

FIG. 1 is a sectional view of a casting material container having a stopper arrangement and a schematic showing of the associated control system;

FIG. 2 is a similar illustration of another embodiment of the present invention having two stopper arrangements therein; and

FIG. 3 is a sectional view to the cast container along the line III-III in FIG. 2.

DESCRIPTION OF THE PREFERRED EMBODIMENTS:

FIG. 1 illustrates a casting material container 1 in a sectional view having an entrance or fill-in chamber through which a passage 48 is connected with a dispensing or exit chamber 11. On the inner wall portion of the fill-in chamber 10 a step or shoulder-like level indicator 47 is provided which lies lower than the bottom surface of the exit chamber 11. The entrance chamber 10 is provided with a filling opening 2 which is hermetically sealed by a cover 3 through which chamber 10 communicates with a control conduit 4 for the purposes hereinafter described. Control conduit 4 has a pressure regulator 17 and a pressure indicator 16 provided therein and is further connected with a source of pressurized medium which can be either a compressor or a pressure bottle which, in turn, by means of a conduit 18a is connected to a central control device 18.

The exit chamber 11 is provided with a stopper arrangement 7 which comprises a stopper 6 and an exit nozzle 5. The stopper 6 has a linkage 8 connected thereto which couples the stopper 6 with a lifting cylinder 9 which, in turn, by means ofa control conduit 13 is connected through a valve 12 controlled by a time controlling device 14 to a conduit 18b leading to the central control arrangement 18. In the wall portions of the exit chamber 11 a level sensor 30 is provided which regulates the level at a value X in the exit chamber 11 as hereinafter described.

FIG. 2 illustrates a casting material container 19 which is similar to the cast container 1 shown in FIG. 1 and consists ofa fill-in chamber 20 and an exit chamber 29. On the inner wall of the till-in chamber 20 there is a step or shoulder-like level indicator 46 which is disposed lower than the bottom surface of the exit chamber 29. The fill-in chamber 20 is provided with an entry or fill-in opening 22 which is hermetically sealed by a cover 21 through which the chamber 20 communicates with a control conduit 23. The latter has provided therein a pressure valve 25 and a pressure indicator 24 and is connected to a source of pressurized medium 26 which, in turn, by means ofa conduit 18a is connected to a central control arrangement which is not shown in FIG. 2; however, it is similar to the one shown in FIG. 1 and identified there by the reference numeral 18. The exit chamber 29 contains a pair of stopper arrangements 44, 45 of which the arrangement 44 is a flow-through stopper arrangement comprising a flow-through nozzle 27 and a flow-through stopper 28 while the arrangement 45 is an exit or dispensing arrangement and contains a dispensing nozzle 31 and a dispensing stopper 32. The dispensing stopper 32 is by means of a linkage 34 connected with a lifting cylinder 35 which, by means of a control conduit 36 through a control valve 37 controlled by a time controlling device 38 and through a conduit 18a, is connected with the central controlling arrangement not shown in FIG. 2 but, as mentioned. is similar to the one shown in FIG. 1.

In the wall portion of the exit chamber 29, similarly as in FIG. 1, a level sensor 33 is provided for purposes hereinafter described.

FIG. 3 illustrates a cross-sectional view taken along the line IIIII1 in FIG. 2, of the arrangement of the flow-through stopper device 44. The flow-through stopper arrangement 28 of the flow-through stopper device 44 is provided with a stopper linkage 42 which is operable by means of a lifting cylinder 43. A control conduit 40 constitutes a connection from the lifting cylinder 42 to a time controlling device 41 operating on a control valve 39 on which, by means of a conduit 18c is connected with the central control arrangement as identified by reference numeral 18 in FIG. 1.

lows:

First the cover 2 of the cast container 1 is removed and liquid metal is poured through opening 2 into the entrance or receiving chamber until it fills it up to the level indicator 47. As a result the liquid metal rises in passage 48 connecting the entry chamber 10 with the exit 11 to a level similar to the level of the indicator 47. Next the cover 3 is replaced and hermetically sealed to the container 1 and thereafter pressurized air or a gaseous medium is introduced into the chamber 10 by means of the control conduit 4 from source whereupon the liquid metal will be forced into the exit chamber 11. The level X" of the liquid metal in the exit chamber 11 is controlled by a metal sensor 30 which by means of the control devices 16, 17 regulates the feed of the pressurized air in such a manner that the level "X" and, thereby, the exit velocity during the time-control opening of the stopper arrangement 7 is retained constant. If it is necessary to empty the exit chamber 11 upon disturbances during the operation or when the stopper arrangement 7 must be freed then the valve 17 is connected to the atmosphere, whereupon the pressurized air can leave the fill-in chamber 10. As a result, the pressure on the liquid metal is reduced whereupon the liquid metal present in the exit chamber 11 returns to the entry chamber 10.

The operation of the device illustrated in FIG. 2 differs from that shown in FIG. 1 in that a pair of stopper arrangements 27 and 45 are present whereby there is a possibility to have several level values present in case this is necessary.

The advantage of the above-described casting arrangement resides in that the metal in the exit chamber of the casting container can be kept at a predetermined constant level whereby a constant exit velocity can be obtained and also in that by reducing the pressure in the entry chamber the exit chamber can be completely cleared.

We wish it to be understood that we do not desire to dispensing chamber; passage means connecting said entry and exit chambers and defining an inlet orifice in the bottom surface of the exit chamber; means for sensing the liquid metal level in the exit chamber; means associated with said sensing means 'for supplying and controlling a gaseous medium under pressure to said entry chamber for translating said liquid metal between said entry and exit chambers and for regulating the level of said liquid metal in said exit chamber at a predetermined constant level;

liquid metal indicator means extending into said entry chamber at a level below the bottom of said exit chamber; and

a controllable stopper arrangement disposed in said exit chamber for controlling the dispensing of said liquid metal therefrom.

2. The combination as claimed in claim 1, wherein said indicator means comprises a level shoulder portion which is disposed lower than the bottom of said exit chamber.

3. The combination as claimed in claim 1, wherein a pair of said controllable stopper arrangements arev disposed in said exit chamber, one of said stopper ar-' rangements for closing and opening of said passage means, the other of said stopper arrangements for the dispensing of predetermined quantities of metal from said exit chamber.

4. The combination as claimed in claim 1, wherein a plurality of said exit chambers are provided for each entry chamber. 

1. In combination, a container for a liquid casting material comprising a receiving or entry chamber and an exit or dispensing chamber; passage means connecting said entry and exit chambers and defining an inlet orifice in the bottom surface of the exit chamber; means for sensing the liquid metal level in the exit chamber; means associated with said sensing means for supplying and controlling a gaseous medium under pressure to said entry chamber for translating said liquid metal between said entry and exit chambers and for regulating the level of said liquid metal in said exit chamber at a predetermined constant level; liquid metal indicator means extending into said entry chamber at a level below the bottom of said exit chamber; and a controllable stopper arrangement disposed in said exit chamber for controlling the dispensing of said liquid metal therefrom.
 2. The combination as claimed in claim 1, wherein said indicator means comprises a level shoulder portion which is disposed lower than the bottom of said exit chamber.
 3. The combination as claimed in claim 1, wherein a pair of said controllable stopper arrangements are disposed in said exit chamber, one of said stopper arrangements for closing and opening of said passage means, the other of said stopper arrangements for the dispensing of predetermined quantities of metal from said exit chamber.
 4. The combination as claimed in claim 1, wherein a plurality of said exit chambers are provided for each entry chamber. 